US3163405A

US3163405A - Homogenizer and mixer for liquids

Info

Publication number: US3163405A
Application number: US249431A
Authority: US
Inventors: Leslie L Balassa
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-01-04
Filing date: 1963-01-04
Publication date: 1964-12-29
Anticipated expiration: 1981-12-29

Description

L. L. BALASSA HOMOGENIZER AND MIXER FOR LIQUIDS 3 Sheets-Sheet 1 Dec. 29, 1964 Original Filed Oct. 1, 1962 FIG INVENTOR. LESLIE L. BALASSA Dec. 29, 1964 1.. L. BALASSA HOMOGENIZER AND MIXER FOR uquzns INVENTOR. LESLIE L. BALASSA 3 Sheets-Sheet 2 Original Filed Oct. 1, 1962 Dec. 29, 1964 L. BALASSA HOMOGENIZER AND MIXER FOR LIQUIDS Original Filed Oct. 1, 1962 5 Sheets-Sheet 3 INVENTOR LESLIE L. BALASSA ATTORNEY United States Patent 9 Claims. ((11. 259-Q7) This invention relates to a mixing device suitable for many purposes, such as mixing, homogenizing, dispersing and pumping. It may be used both in laboratories and in production in the preparation of emulsions, vegetable gum and starch dispersions, and for the dispersion of finely divided solids in liquids, such as pigment dispersions. This invention greatly improves the adaptability and etiectiveness of a mixing machine.

This is a continuation of application Serial No. 227,515 filed October 1, 1962, now abandoned.

The machine of this invention mixes, blends, homogenizes, and disperses emulsions, solutions and dispersions. Due to the unique construction of the turbine rotor and stator members of its operating head, themachine is particularly adapted top-recess emulsions and dispersions, which are much higher in viscosity and more highly thixotropic, more effectively than it has been possible to equal with other types of enclosed turbine devices heretofore used.

The construction is such that the machine can be used as a closed turbine mixer or, by a single operation, as an efiicient open turbine mixer. By util zing certain adjusting means to decrease the space horizontally between the operating parts of the head, theirhomogenizing and dispersing action can be increased, and conversely, by increasing said spacing their purnping, blending, and mixing action can be increased as well as the capacity of the machine.

With mixing devices of this type when a sleeve is fixed in position surrounding the rotor, the device is operated as a closed turbine unit, and the flow of liquid is through the sleeve along the axis of the mixing device, which normally is vertically upwards. When the sleeve is removed, the device is operated as an open turbine unit, and the entire mass of liquid in the vessel rotates about the axis of the device creating a vortex. The vortex incorporates air into the liquid which is often undesirable, and reduces mixing efiiciency.

In the prior art etforts were made to correct the undesirable effects of open turbine operation. Baflies were introduced into the mixing vessel to control movement of the liquid about the axis of the mixing device. These bellies were costly, increased the difficulty and time of clean-up and interfered with the 'mixing eiiiciency of the device when it was operated as a closed turbine unit. Further, the mixing device had to be securely clamped into position when. operated as an open turbine mixer because of its tendency to whip around under the pressure of the open rotor operating at high speed and under the influence of the rotating liquid.

Heretoiore, efforts were made at easy convertibility of mixing devices from open to closed turbine operation. One example is shown in applicants copending application, Serial No. 84,821, which has a removable sleeve.

While the construction taught in that application wa a great improvement over the art, it was practicable'only with devices that could be removed from the mixing vessels. Removing or replacing the sleeve after an operation to convert the device is messy and wasteful of material. I V

Thepresent invention overcomes these shortcomings in prior art devices in an easy, facile manner. In accordance with the present invention, a mixing device can be converted from a closed turbine operation to an open turbine operation or vice versa, by controls remote from the mixing head, without removing'the head from the mixing vessel. Thus, the largest units, including those fixed permanently into the mixing vessel can be converted easily from one to the other type of operation quickly with little down time.

Another advantage of the present invention is when the unit is operated as an open turbine operation, bafiles are automatically provided which prevent the formation of a vortex and direct the flow of liquid toward the periphery of the mixing vessel and a quantity of liquid between the stator vanes. This muiti-directional flow provides excellent mixing characteristics and eliminates any stagnant pools of material in the mixing vessel.

Other objects and advantages of the invention will be apparent from the following description and accompanying drawings, in which drawings:

FEGURE l is a side elevational view of a mixing machine embodying the invention in the closed position;

FKGURE 2 is an enlarged sectional view ofthe vane operating mechanism of the machine taken along lines 2--2 of FlGURE 1;

FIGURE 3 is an enlarged crosseectional view of the operating head taken along lines 3-3 of FIGURE 1;

FIGURE 4 is an enlarged fragmentary detail view in elevation of the operating head showing the vanes in open position; 7

FIGURE 5 is an enlarged view showing the vanes of the operating head in the open position; and

FEGURE 6 is a dir'ierent embodiment of the operating head.

Referring to the drawings, and particularly to FIGURE 1, the mixing machine comprises a motor it mounted in an upright position with its lower end attached to a motor support bracket 12. Bracket 12 may be clamped or held vertically in any convenient manner not shown. Depending downwardly from bracket 12 are a series'of guide or support rods 16, there being four rods shown in the drawings, with their lower ends secured to an operating head 20 relatively remote from the motor and in vertical alignment therewith.

Motor 1% has a drive shaft 22, and beneath in vertical alignment therewith is a driven mixer shaft '24. The lower end of drive shaft 22 is connected to the upper end of the mixer shaft 24 by a coupling 26.

' Operating head 26? comprises a stator 3d, and a turbine rotor 46. Stator 36 consists of a central hub part and a plurality of spokes or vanes 31 integral therewith and radiating outwardly therefrom, with their outer ends open, and being suitably spaced apart to provide what may be termed jet openings therebetween forming passage- Appropriate members of ways for the fluid solution. spokes 31 are secured to the lower ends of guide rods 16, in any convenient manner, such as by threaded engagement, s ecial fittings, clamps, etc.

The lower end of shaft 24 is stabilized by being slidably journalled in the hub of'stator fit? as shown in PEG- URE 4, and turbine rotor 49', which is preferably stainless steel, is attached to shaft 2 5 in close proximity to stator 30. As shown, rotor 49 is attached to shaft 24 by a nut 41 acting against a shoulder of shaft 24. Rotor tilt is precision engineered, tempered and'balanced for high.

of stator 30, and their trailing edges 48 are also parallel with surfaces 32 but closely associated therewith to provide a hydraulic shear when the blades 42 are swept across surfaces 32. This configuration of blades 42 forms a wedge-like area between the blades and surfaces 32 which progressively diminishes rapidly as the trailing edges 48 approach during the whirling of rotor 40. It will be understood that simultaneously the leading edges sweep through the fluid, so that the latter will be directed vertically upward .by the pitch of blades, and fed through the hydraulic shear of the trailing edges, and on through the jet openings between adjoining spokes 34.

Surrounding rotor 40 is a sleeve 60 shown best in FIGURES 1 and 3. As shown, sleeve 60 is open ended and has a generally square outer shape having four sides, 62, 64, 66 and 68. The inner surfaces of

sides

62, 64, 66 and 68 are curved to form a cylindrical surface about rotor 40, as best seen in FIGURE 3. Sleeve 60 may take other shapes as will be indicated hereafter. As

shown, sides 62, 64, 66 and 68 taper inwardly at their lower edges. Nut 41 securing rotor 40 to shaft 24 extends below the lower edges of

sides

62, 64, 66 and 63 to provide space for fluid to pass when nut 41 rests on the floor or bottom of the container for preventing the operating head from being sucked against the bottomof the container, not shown, during operation.

The operating head of the present invention may be converted into an open turbine mixer in a simple, facile manner. Each of

sides

62, 64, 66 and 68 is pivotally mounted to a selected radially extending stator spoke 31, as best seen in FIGURE 5. Extending radially outwardly from the hub of stator 36 are four

arms

72, 74, 76, and 78, which support sides 62, 64, 66 and 68 respectively, when they are in the closed position, as best seen in FIGURE 3.

Attached to the pivoting mechanism of

sides

62, 64, 66, and 68 are vertically extending

rods

82, 84, 36, and

, 88 respectively. As shown, these rods are coupled to their corresponding sides by a pin to allow for easy disassembly.

Rods

82, 84, 86, and 88 extend vertically upward through motor bracket 12.

Rods

82, 84, 86, and 88 are preferably rotated'simultaneously and in the same direction in an are sufficient to pivot each of

sides

62, 64, 66, and 68 of sleeve 60 substantially an equal amount. One manner of accomplishing this is shown in FIGURE 2. Disposed between consecutive sprocket wheelsmounted on the ends of rods 82,

84, 86, and 88 are sprocket wheels 99, 92, 94, and 96,

respectively. These sprocket wheels are attached to their respective shafts in any convenient manner, such as by keys or splines.

Rods

82, 84, 86, and 88 are journalled on a support plate 98 mounted on bracket 12. Disposed v between adjacent sprocket wheels is an idler wheel. In-

terposed between sprocket wheels 90 and 92 is an idler.

is an idler wheel 104, and between sprocket wheels 96 r and 90. is an idler wheel 166. Engagingthe sprocket wheels and idler wheels in a manner as shown in FIG- URE 2 is a continuous chain belt 1168. Belt 163 is rotated by means of a sprocket gear 116 coupled to a .hand wheel 112 Rotation of hand wheel 112, counter clockwise, as shown in FIGURE 2, actuatcs chain belt 108, as shown by

arrows

114 and 116. It is seen that sprocket wheels 90, 92, 94 and 96 all rotate in the same direction, counter clockwise, which in turn rotates their

corresponding rods

82, 84, 86, and '38 counter clockwise, so that sleeve sides 62, 64, 66, and 68 respectively, are opened to the position shown in FIGURE 5. While. a hand wheel mechanism is shown actuating rods-82, 84, 86, and 88, other actuating means may be used such as a motor, various drives, belt and gear arrangements.

When sleeve is converted into open turbine position,

as shown in FIGURE 5, sides 62, 64, 66 and 68 act as vertical baflles and direct the liquid flow from rotor 40 toward the periphery of the mixing vessel, not shown, with great force. Further, the back pressure caused by these bafiles forces a quantity of liquid to move between stator spokes 31 resulting in an excellent mixing effect in the entire mass of liquid with no formation of stagnant pools of liquid within the mixing vessel, or a vortex in the liquid.

Sides

62, 64, 66, and 68 are opened to any desired angle, as viewed in FIGURE 5, giving a variety of mixing characteristics. When fully opened, they act as vertical baffles. When partially opened, back pressure is increased resulting in a greater quantity of liquid moved between the vanes of the stator.

When the sides are in the open position, material adhering to the outer surfaces of sleeve 6%) can be removed since the liquid issuing between the sides, flows past the outer surface of an adjoining side with sulficient force to remove any adhering material. This saves much time consuming and messy manual operation.

Another embodiment for rotating

sides

62, 64, 66, and 68 of sleeve 60! is shown in FIGURE 6. Coupled to the pivoting mechanism of

sides

62, 64, 66 and 68 are

arms

120, 122, 124, and 126, respectively. Each of

arms

120, 122, 124, and 126 has a sprocket wheel 128 mounted thereon above the upper edges of corresponding sides 62,.

64, 66, and 68. Concentrically disposed about driving shaft 24 is a sleeve 139. Sleeve 139 may be journalled in support bracket 12. Mounted on the outer surface of sleeve 130 adjacent its lower end are gear teeth 132 for cooperatively mating with sprocket wheels 128. R0- tating sleeve 139 will rotate sprocket wheels 128 which in turn rotate

arms

120, 122, 124, and 126. Sleeve 130 may be rotated in any convenient manner. If desired, gear teeth may be cut in

arms

120, 122, 124 and 126, and sleeve 130.

Advantageously, material may be introduced down sleeve 136 into the machine or withdrawn. Liquid or comminuted material may be introduced via shaft 130 and dispersed by centrifugal force by rotor 42 into the stator 30. By this manner, or by reversing the procedure, a close or coarser relationship of the stator and rotor parts of the operating head may be accomplished tosele'ctively obtain a finer or coarser granulation of the particles in suspension in the emulsion in the container.

If desired, a baffle plate, not shown, may be adjustably positioned generally perpendicular to the axis of shaft 24 and above the operating head 20 by suitable means. The baflle plate effectively deflects horizontally the material surging through the operating head so that the desired circulation will be established.

It will now be seen that the mixing machine is not only adaptable for use both as an open or closed turbine mixer, but operates efficiently since the rotor is shaped to pump material through the operating head with great may occur to other persons skilled in the art, which might be employed for various adaptations to other useful purposes within the scope of the invention claimed.

What is claimed is:

1. A mixing device for mixing material within a container comprising a mixing head for operation within said container, said mixing head comprising a stator and a rotor, the stator comprising a central hub and a plurality of 5130 135 radiating therefrom, each of said spokes having a smooth under-surface inclined upwardly and outwardly and dea relatively sharp angle to the axis of said head, said rotor having a plurality of fan-like blades each tapering upwardly and rearwardly and having a pitch substantially corresponding to the angle of said undersurface of said spokes, the leading and trailing edges of said blades rotating in a plane substantially parallel to the under-surfaces of said spokes with the leading edge being more remote therefrom than the trailing edge, a remote drive shaft for said rotor, a mixer shaft vertically aligned with said drive shaft and having its lower end journalled in and extending below said stator, said extending end being connected to said rotor, means coupling the facing ends of said drive shaft and said mixer shaft, means rotating said drive shaft, means supporting said drive shaft, said stator being journalled to said mixing shaft at a predetermined distance fromsaid supporting means, a plurality of side elements pivotally connected to selected ones of said stator spokes, said sides when in closed position forming an open ended cylindrical sleeve surrounding said stator spokes, and means for pivoting said sides outwardly away from said rotor into open position so that said mixer can be readily converted a from closed to open turbine operation.

2. A mixingdevice for mixing material Within. a container comprising a mixing head for operation within said container, said mixing head comprising a stator and a rotor, the stator comprising a central hub and a plurality of spaced apart spokes radiating therefrom, each of said spokes having a smooth under-surface which is inclined upwardly and outwardly and defining a relatively sharp angle to the horizontal, said rotor having a plurality of fan-like blades each taperin 'upwardly and rearwardly and having a pitch substantially corresponding to said angle of the'under-surface of said spokes so that the leading and the trailing edges of said blades rotate in planes substantially parallel to said under-surface of said spokes with the leading edges of said blades being more remote therefrom than said trailing edges, said trailing edges being in hydraulic shearing relation to said under-surfaces, remote drive means for said rotor, a shaft connecting said drive means to said rotor, means journalling said stator on said shaft abovesaid rotor, means coupled to said shaft for moving said shaft longitudinally with respect to said stator for varying the spacing between said blades of said rotor with the under-surface of said stator, a plurality of side elements pivotally connected to selected ones of said stator spokes, said side elements when in closed position forming an open ended cylindrical sleeve surrounding said stator spokes and means for pivoting said side elements outwardly away from said rotor into open position so that said mixer can be readily converted from closed to open turbine operation.

3. A mixing device for mixing material within a container comprising a mixing head for operation within said container, said mixing head comprising a stator and a rotor, the stator comprising a central hub and a plurality of spaced apart spokes radiating therefrom, each of said spokes having a smooth under-surface which is inclined upwardly and outwardly and defining a relatively sharp angle to the horizontal, said rotor having a plurality of fan-like blades each tapering upwardly and rearwardly and having a pitch substantially corresponding to said angle of the under-surface of said spokes so that the leading and the trailing edges of said blades rotate in planes substantially parallel to said under-surfaceof said spokes, with the leading edges of said blades being more remote remote drive means'for said rotor, a shaft connecting said drive means to said rotor, means journalling said stator on said shaft above said rotor, a plurality of side elements pivotally connected to selected ones of said stator spokes, said sides when in closed position forming an open ended sleeve surrounding said stator spokes and means for pivoting said sides outwardly away from said rotor into open position so that said mixer can be readily converted from closed to open turbine operation.

4. In a machine for mixing liquids in a container, comprising driving means, an operating head coupled to said driving means by a shaft, said head including a stator, and a rotor, the stator being supported in a fixed horizontal position with respect to said driving means and remote therefrom, and comprising a central hub part and a plurality of spokes radiating therefrom, and being open ended, said shaft havingits lower end journalled in and extending below said stator and having said rotor attached thereto, said stator spokes having fiat under-surfaces inclined upwardly in an outward directiondefining a'relatively sharp angle to the horizontal, and said rotor constituting a plurality of flat fan-like blades having a pitch substantially corresponding to the angle of the said under-surface of the stator spokes, so that the leading and the trailing edges of said blades rotate in a plane sub-' stantially parallel with said under surfaces with said leading edges relatively remote therefrom, and the trailing edges in hydraulic shearing relation thereto, and an adjustable open ended cylindrical sleeve surrounding said stator spokes, said sleeve comprising a plurality of sections each hingedly connected to selected spokes and adapted to enclose the space between consecutive spokes when in the closed position, said sections being pivotable generally radially to open position, and actuating means for pivoting said sections, said actuating means being remote from said sections.

5. A mixing device for mixing material within a container comprising a mixing head for operation within a container, said mixing head comprising a stator shell and a rotor having a blade within said stator shell, said stator shell having a plurality of pivotable sections, remote drive means for said rotor, a drive shaft connecting said drive means to said rotor and means for pivoting said sections of said stator shell relative to said rotor so that said mixer can be readily converted from closed to open turbine operation.

6. A mixing device for mixing material within a container comprising a mixing head for operation within a container, said mixing head comprising a stator shell and a rotor having a blade cooperatively positioned with repect to said stator shell, said stator shell having a plurality of pivotable slides, remote drive means for said rotor, a drive shaft connecting'said drive means to said rotor, gear teeth operatively connected to each of said sides of said stator shell and disposed concentrically about said drive shaft, said sides being pivotable when said gear teeth are rotated, a hollow shaft concentrically and rotatably mounted about said drive shaft, and having gear teeth about its outer surface, said gear teeth cooperatively engaging each of said first mentioned gear teeth, and means remote from said mixing head for rotating said hollow shaft and pivoting said sidesrelative to said rotor so that said mixer can be readily convertedfrom closed to open turbine operation.

7. A mixing device for mixing material within a container comprising a mixing head for operation within therefrom than said trailing edges, said trailing edges being in hydraulic shearing relation to said under-surfaces,

a container, said mixing head comprising 'astator shell and a rotor having a blade cooperatively positioned with respect to said stator shell, said' stator shell, having a plurality of pivotable sides, remote drive means for said rotor, a drive shaft connecting said drive 'means'to said rotor, a gear wheel coupled to each of said sides, said sides being pivotable when said gear Wheels are rotated,

and means for rotating said gear wheels in the same direction and pivoting said sides relative to 'said rotor, so that and a rotor having aiblade cooperatively positioned with respect to said stator shell, said stator shell having a plurality of pivotable sections, remote drive means for said rotor, a drive shaft connecting said drive means to said rotor and means for pivoting said sections of said stator shell relative to said rotor to a'selected angle with respect to the axis of said stator shell, so that said mixer can be converted from closed to a desired open turbine operation.

9. A' mixing device for mixing material within a con tainer comprising a mixing head for operation Within a g container, said mixing head comprising a stator shell and a rotor having a blade cooperatively positioned with respect to said stator shell, said stator shell having a plurality of pivotable sections, remote drive means for said rotor, a drive shaft connecting said drive means to said rotor and means for pivoting said sections of said stator shell relative to said rotor so that said mixer can be readily converted from closed to open turbine operation.

References Qited in the file of this patent UNITED STATES PATENTS 861,893 Pool July 30, 1907 1,733,244 Smith Oct. 29, 1929

Claims

9. A MIXING DEVICE FOR MIXING MATERIAL WITHIN A CONTAINER COMPRISING A MIXING HEAD FOR OPERATION WITHIN A CONTAINER, SAID MIXING HEAD COMPRISING A STATOR SHELL AND A ROTOR HAVING A BLADE COOPERATIVELY POSITIONED WITH RESPECT TO SAID STATOR SHELL, SAID STATOR SHELL HAVING A PLURALITY OF PIVOTABLE SECTIONS, REMOTE DRIVE MEANS FOR SAID ROTOR, A DRIVE SHAFT CONNECTING SAID DRIVE MEANS TO SAID ROTOR AND MEANS FOR PIVOTING SAID SECTIONS OF SAID STATOR SHELL RELATIVE TO SAID ROTOR SO THAT SAID MIXER CAN BE READILY CONVERTED FROM CLOSED TO OPEN TURBINE OPERATION.